ATX rpm limiter???

[Arc Angel]

Hello again, guru's. Strange problem, with a strange question. I remember reading somewhere in the forum about the ATX SHO's having an rpm limiter when the trani is in PARK. Something about the torque converter not letting the rpms get above 3000.
My problem, which I have brought up before in the forum -
When my one ATX SHO is climbing a hill (highway speed), right at 3000 rpm, it starts bogging, i.e. just as if this "rev-limiter" is kicking in. I've tried about every possible fix in the book to address this issue, and, it would seem the most logical suspect is now this item (RPM Rev Limiter is engaging at 3000 RPM while the car is out of drive and running down the highway!).
Any clues if there is a way to DISCONNECT this darn thing, and, more importantly - How to disconnect it. Or, second choice would be if there was a way to FIX it, since it is obviously malfunctioning.
Thanks once again for any replies. Much appreciated.

Frank Germano

 

[Shoaz]

It's doubtful that's your problem since the ATX P/N rev limit is 4k, not 3k.

And there's no benefit to disabling it, since if you're in D/2/1 or Reverse the 4k rev limit is turned off.

 

[Racer X]

...unless he has an inaccurate tachometer.

The P/N rev limiter is at 4k. Put your car in park, and floor it. If it stops at 4k, then your drivability problems are rooted elsewhere. If the needle stops at 3k, then you have a bad tach in addition to a malfunctioning MLP sensor, commonly known as a neutral safety switch. You can find it atop the transmission at the end of the gear selector cable.

 

[HootUSMC]

Speed sensor on tranny screwy?

 

[Arc Angel]

Well...here's what's happening with this 94 ATX SHO -
This car runs great, when it's on flat level ground. WOT and she runs strong. Start climbing any grade, i.e. a hill on the highway (which are all over the place up in Pennsylvania) and right around 3000 RPM, it "boggs" down, bad. Ever drive a little 4-banger and have the AC clutch engage and the engine just boggs down? Well, multiply that by five, and that's what it feels like.
Once it boggs down, if I let my foot off the accelerator pedal, and then jump back in, there is a delay for about two seconds, and then the engine pulls regularly, again. I'd sware I'm either loosing a cylinder or two during this bogg, or, that transmission governor/limiter is kicking in. I mean it just boggs down, looses power, and down-right yuck at hill-climbing power. Then, just as fast as it happens, it will kick back in with full power for a while (still climbing a hill) go like all ****, then do it again! Level off and/or start going downhill and the darn car runs fine. Strange, to say the least.
That's about as best as I can describe it. Any ideas as to what the heck would cause this kind of problem (bogging, but only when going UP HILL) would be appreciated. I've lived with this for over six months. Replaced coil pack, DIS module, plugs, wires, starter, battery, battery cables, IAC, cleaned intake manifold, intake manifold and spark plug well gaskets, Cam seals, all vacuum lines...you name it (just during regular mechanical needs getting the car back to 100%).
Thanks again for any ideas...
Frank Germano

 

[JustinSane]

heh i know what you mean about the hills here in PA, any way if you jack up the car and put the front on jackstands and run it in drive does it do it then? try and determin if its the load of a hill on the drivtrain or the angle it self. if its the angle you may have a loose ground wire or other wire thats swinging to and fro.

 

[SHOZ123]

Got plenty of gas in the tank?

 

[Shoaz]

Sounds like a load-related issue, but not anything to do with the P/N rev limiter.

 

[Arc Angel]

Plenty of gas, definitely, and even a new fuel filter and fuel pump. I've thought about the "loose wire" part...but...which one and where would it be located to drag an engine down as significantly as this is doing - and - only when going uphill, i.e. at a steeper angle??? Me thinkest it's about time to eBay her if I can't figure this one out, as it's driving me crazy.:laugh_ti:
If this helps any - when this little "bogg" happens - the RPM's do drop about 100 to 200 or so, briefly...Like I said - new coil, spark plugs, wires, DIS module (and it's totally clean behind and getting good ground, all vacuum lines new and none leaking, intake cleaned, new gaskets, EGR is new, IAC is new, all ports to EGR and intake cleaned, MAF cleaned, K&N filter, running Castrol Syntech oil, with Lucas Synthetic additive, K&N Oil filter...CAT's where cleaned out when I got the car (someone took out all the CAT's inner stuff - they're just open cans, right now), exhaust is in excellent shape, otherwise...no leaks or cloggs.
So...we're either talking a short (intermittent and only at hill angles), a glitch with this Governor/Rev Limiter on the trani, a cylinder or two dropping out intermittently (uphill only)...or WHAT?! HELP...
Frank
Frank

 

[SHOZ123]

Could be the TC screwing up.

If it were the rev limiter it would be missing as the fuel would be shut off to certain cylinders.